Sharapova had been the most dominant player in the women's draw so far, recording successive 6-0 6-0 victories in the first two rounds before she dispatched seven-times grand slam winner Venus Williams with contemptuous ease in the third round.

The second seed, however, took time to get into her match against the 27-year-old Flipkens and while she won the first set 6-1, it took 43 minutes which demonstrated how difficult she found the tenacious Belgian to put away.

Sharapova, however, cranked into gear in the second set to clinch it in 25 minutes and set up a quarter-final against fellow Russian Ekaterina Makarova after the 19th-seed dispatched fifth seed Angelique Kerber 7-5 6-4.

Elsewhere, Li Na won 7-6 6-1 against Julia Goerges to reach the quarter-finals. The former Australian Open finalist was made to work hard in the first but came out on top winning the tiebreak 8-6 before winning the second set in 32 minutes.